Cutting implement drive means



June 17, 1952 E. E. wETTLl-:Y

QUTTING IMPLEMENT DRIVE MEANS 2 SHEETS-SHEET 1 Filed June 28. 1946- June17, 1952 E. E. WETTLEY 2,601,193

CUTTING IMPLEMENT DRIVE MEANS Filed June 28, 194e 2' SHEETS-SHEET 2 MEIMaf@

Patented June 17, 1952 UNITED STATES PATENT OFFICE CUTTING IMPLEMENTDRIVE MEANS Eberhard E. Wett-ley, Chicago, Ill.

Application June 28, 1946, Serial No. 680,149

(Cl. 'i4- 89) 9 Claims.

l rlhis invention relates to a cutting implement or tool, and morespecifically to a trimmer for convenient use in and about a garden tocut away grass, trim hedges and other perennial shrubs,

'cut weeds, thin out excessive growths, etc., and

one of the main objects thereof is to provide a. light weight, compactcutting tool at a reasonable cost and one which is capable of free andeasy manipulation with a highl degree of efficiency.

Another object of the present invention is to provide a cutting toolhaving mechanism producing continuous rapid cutting action allowingrelatively fast bodily movement of the tool, without pause orinterruption, over areas being trimmed.

It is a further object of this'invention to make a cutting tool of thischaracter having a rapid and continuous cutting action whichincorporates a comparatively slow operating mechanism that is well ttedfor hand manipulation. This relieves excessive hand strain in operatingthe cutting tool.

It is another object of this invention to provide a cutter as above setforth which may be provided with a long waist level column or a shortcolumn, each including a handle providing hand grip means connected withthe actuating mechanism of the cutting blades to operate such mechanism.And as indicated, the operating mechanism is designed to produce a rapidcutting action of the cutting blades through hand operated meansrequiring relatively slow speed manipulation. By using a slow speed handgrip unit at the end of the column for actuating the operatingmechanism, it is therefore, a convenient and efficient arrangement thatdoes not produce hand fatigue and yet obtains a rapid cutting action.Furthermorathe same hand grip means or handle arrangement provides thenecessary elements for moving and guiding the tool over and into variousareas which are being worked upon by the cutting implement.

The cutting tool, as another feature, may also include adjustablemechanism to permit changing the angular relationship between theoperative cutting plane of the cutting blades and the axis of thesupporting column or handle structure therefor. This will simplifyworking under relatively large shrubs or in other remote spots. Theblades may, in some instances, be moved substantially in line with thesupporting column to reach large bush tops or certain tree branches totrim such growths.

Although several forms of cutting implements are shown and described,such are merely for the purpose of illustrating various applications ofthe principles set forth under the fundamental generic concept of theinvention. It should further be understood that various forms of cuttingmechanisms could be operated by the same structures here typified by theexamples illustrated. Any coacting cutting means operable by relativemovement therebetween may be used and suitably connected with theoperating mechanism of this invention which is capable of producing suchrelative movement in a cutting means. To simplify the disclosure and thedescription a pair of conventional relatively movable reciprocatingcutting blades are illustrated. Such blades are shown as having dualcutting edges to enhance the usefulness of the implement by permitting aback and forth motion much in the manner that a grass whip cutting toolis manipulated, but considerably slower, however, since the action is aprogressive cutting action and not a striking action.

All other objects, and advantages and further details relating to othervariations in the design and arrangement of the cutting implement of thepresent invention shall hereinafter appear from the following detaileddescription referring directly to the disclosures and the drawingsforming a part of this specication.

In the drawings:

Figs. lA and 1B considered together typ-ify a general construction ofcutting implement incorporating the principles inherent in the cuttingtool of the present invention and illustrate one application of thegeneric principle involved; certain of the parts thereof being brokenaway and in section to clearly emphasize some of the details ofconstruction thereof;

Fig. 2 is a fragmentary illustration of a portion of Fig. 1B withcertain Darts thereof in elevation to more clearly show part of theactuating mechanism of the cutting blades;

Fig. 3 is a transverse cross sectional view taken substantially alongthe line 3-3 in Fig. 1B;

Fig. 4 is a fragmentary plan View of the cutting blade mechanism of Fig.1B illustrating a conventional type of blade construction;

Fig. 5 is another'transverse cross sectional view taken substantiallyalong the line 5-5 in Fig. 1B;

Fig. 6A is a sectional view of an adjustable .construction of cuttingimplement wherein the actuating elements thereof are somewhat rearrangedto be positioned parallel to the cutting blades and immediately adjacentthereto;

Fig. 6B 'is a side elevational view of the handle 3 end of Fig. 6A toillustrate details of tthe manual parts of the adjustable mechanism;

Fig. 7 is a plan view of the structure illustrated in Fig. 6A with partsthereof broken away and in section;

Fig. 8 is a vertical cross sectional view taken substantially along theline 8 8 in Fig. 6A;

Fig. 9 is another vertical cross sectional view taken substantiallyalong the line 9-9 in Fig. 6A;

Fig. 10 is an axial cross sectional view of a fragmentary portion of acutting implement illustrating still another modified arrangementthereof but incorporating the same general principles set forth by thepresent-invention;

Fig. 11 is a transverse cross sectional view to illustrate certainstructural details -as seen substantially in the plane of the line II-Hin Fig. l; and

Fig. 12 is a fragmentary view further illustrat ing other details ofconstruction of the Fig.

cutting implement and substantially as seen along the plane of the lineI2-I 2 as indicated in Fig. 10.

Referring now to Figs. 1A, 1B, and'2 to 5, inclusive, the cuttingimplement here shown comprises a pair of coacting cutting blades I and 2of which blade I 4is stationary'while blade 2 is reciprocated withrespect to blade I, and an actuating mechanism for operating said bladesgenerally indicated by the reference numeral '3 and confined within ahousing-l to which thestationary blade I is secured. Anactuator`5conne'cts with the actuating mechanism y3 land is housed in awaist level column yl with its upper end 1 -pivotally connected at'zwith va'handle or hand grip 9 that is pivotallycarried at I0 by thewaistlevel handle II which is iixedly connected at I2 to the upper end of theywaist level column B.

Relative movement between'the handle members 9 and II from the full lineposition in Fig. 1A to the dotted line position therein causes endwiseshifting of the actuator 5 operating the actuating mechanism 3 which isconnected by means of the motion transmitting mechanism I3 'with themovable blade 2 for impartingreciprocation to the latter blade withrespect t'o the x'ed blade I to obtain the cutting action of theblades.In addition, the handle or hand grip members 9 and I I form a'means forguiding the cutting implement over the areas which are being worked uponand, at the same time, Vprovide means for actuating the blades. Inaddition, a further handle I4 as indicated in Fig. 1A may be secured ina suitable position upon the Waist level tubular column 6 to afford ameans which may be held by the other hand as an additional guide meansfor the cutting tool.

The actuating mechanism 3 of the cutting implement comprises a spiralmember I5 forming an integral part of the actuator 5 which passesthrough a slot I 5 asbest indicated in Figs. 1B and 3 whichis formed inthe upper end of the rotatable sleeve II that is guided -for rotationabout the operating axis of -the spiral member I5 by means of the wallsof the housing 4. As shown in Figs. 2 and 5, the lower end-of therotatable sleeve I'I is provided with cam projections I8 which cooperatedirectly with cam follower projections I9 formed on the guiding andreciprocating sleeve 20, or otherwise 'secured therto,`for the purposeof producing a quick reciprocatory action of the sleeve whenever therotatable sleeve I 'I is revolved bythe spiral member I5.

The lower end of the rec'iprocatory-guide sleeve 29 is slotted at 2I and22, and-carries'a cross pin 23 which engag'es'within the-bifurcated lleg2li`V of a bell crank 25 pivoted at 25 and having its other leg 21operating within the opening 2S of the movable blade 2, this latterdescribed structure comprising the main elements of the motiontransmitting mechanism I3 which reciprocates blade 2 through thedescribed action obtained by the actuating mechanism 3.

Actuator 5 is normally drawn upwardly by a squeeze of the hand upon thehand grip member 9 and II and a" spring 2'9fof selected strength andtension is connected atl'30 tothe spiral I5 and loops about pin 23 ofthe motion transmitting mechanism I3. This spring 29 furnishes powermeans'for returning the spiral member I5 substantially into the positionindicated in Fig. 1B afters'uch'member has been raised or moved endwisewith respect -to the tube B by means of the hand grip members 9 and IIfrom the full line -positionto the dotted line position indicated inFig. 1A. The saine spring 29 also performs the dual'function of ralwaysretracting blade 2 into its extreme left position as shown in Fig. lsince the spring is looped over the pin 23, and through the action ofthebellV crank 25 the tension of the spring is transmitted `to blade 2urging the same into'the housing 4 of the cutting implement.

There are 'various Ways in Which'the cutting blades I and2 maybe held inoperative relation with respect to each other and properly guided toproduce'an efficient cutting action. Onesuch method is illustrated inFigs. 1B and 4 wherein the stationaryblade I isprovided with a stud -3I'projecting through the longitudinal slot 32 in blade 2 whichlreciprocates relatively to blade I, and by providing any suitable cupspring Washer 33 which bears against the under surface'of the blade 2holding the same 'in operative contact with blade I so that the cuttingteethy 34 of blade I reciprocate immediately adjacent the cutting teeth35 of blade 2.

The operation of the cutting implement wherein relatively slow handaction at the hand grips 9 and II will produce a rapidrelativereciprocation between the cutting blades I and-2 is possiblethrough the particular construction hereinbefore described withvreference to Figs. 1A, 1B. rand Figs. 2 to '5,inclusive. Bymanipulating the hand grip member Sand I I land due to spring 29,the/actuator rod 5 is manipulated endwise mov ing the'spiral I5 back'andforth within the tube -5, the spiral-being partially guided in tube 2Glikewise. The actuator 5 isa rod providing a non-rotatable 'element Ydueto its connection at thepivotal point with the hand grip 9 so that thespiral I5 moves bodily endwise -and has'no rotation whatever. "Upward'movement of the spiral I5 is caused bythe hand operation del' scribedwhile downward'movement is affected by the spring 29.

"tionlis capable of quickly reciprocating the sleeve y29 through theaction ofthe cam means I8 and I9 making the'pin23 actuate the bell'crank25 `in the same rapidsequence. 4By vrocking such bell "crank," motionis'directly transmitted to the mov- 'ableblad'e 2`by'means 'of leg 2l ofthe bell crank V25 which engages withih'op'ening 28 of the movable blade'2.

l lSleeve 2`0 is guided for rotation Withinthe rotating sleeve I'I andalso by means of the indented bead 36 for-med'within the hous- -ing 4,and, sincethe'beh'crank 25 only moves in ualplane fat righ-t angles 'to-the 'axis of the pivot pin 26, the bifurcated end 24 of the bell crankextending through slots 2l `and. 22 of the guide sleeve 28 holds suchsleeve against rotation and' only permits reciprocatory movementthereof. The spring 28 at all times holds the sleeve 28 and its cammeans I8 in operative engagement with the cam means I8 of the rotatablesleeve I1. Spring 28 is guided and positioned within the reciprocatoryguide sleeve 28, which together with all of the other described coactingparts of the operating mechanism 3, produces a very compact and simpleyarrangement to obtain a rapid reciprocation of the blade 2 by means ofa comparatively slow squeezing action between the hand grips 9 and ll.

rIhe relatively movable parts of the actuating mechanism and of theother mechanisms of the cutting implement can be so shaped and designedsleeve 28 is guided Aby the housing bead 35 and necessary clearance isprovided between this sleeve and the sleeve I1 for the properfunctioning of the actuating mechanism. Furthermore, a suitable oil holesuch as indicated at 38 in Figs. 1B and 2 is all that is necessary foroiling the entire operating mechanism of the device aside from thehandle portion thereof which only includes the pivotal connections 8 andI0 and these can be easily oiled through the slot 40 and from betweenthe two hand grips as is obvious from the disclosure in the drawings.The blades can be oiled through suitable oil holes such as 40a indicatedin Fig. 4.

Referring now to Figs. 6A, 6B, 7, 8 and 9, inclusive, the cutting bladesare here indicated as 4I and 42. In this construction, the waist leveltube is shown at 43 and is pivotally connected at 44 to a horizontallydisposed tube 45 which houses the actuating mechanism 46 and carries thecutting blades 4I and 42. In this construction, the blade 4I issoldered, brazed, or otherwise secured as at 47 to the under side of thehorizontal tube 45. Suitable spring units such as 48 guide the movableblade 42 with respect to the blade 4I and also hold the blades inoperative contact therewith.

In this construction, a similar hand grip means such as shown in Fig. 1Acan be employed for actuating a wire or cable 48, or any other suitableilexible non-expandable mechanism can be connected at 58 to one end ofthe spiral 5l. The spiral l carries a relatively long ilat portion 52which is not twisted and is guided in a plug 53 having a slot 54 shownin Fig. 8 for preventing rotation of the spiral 5l during the endwisemanipulation thereof. While upward movement of the wire 48 causes thespiral 5I to move to the left as seen in Figs. 6A and '7, a spring 55 ofsuitable size and tension is connected at 56 to the opposite end of thespiral 5l and to the end plug 5'! shown in Fig. 7 which closes the outerend of the tube 45 and also holds the adjacent end of the spring asindicated. The spring 55 therefore cooperates with any suitable handmanipulating device for moving Wire 49 in the opposite direc- Vwithinthe tube 45 and is held against endwise movement by any suitable meanssuch as pins 59 and 50 shown in Fig. 6A. As indicated in Figs. 6A and 9,one end of the sleeve 58 is provided with a suitable slot 6l throughwhich the spiral 5I passes causing the sleeve 58 to rotate during theendwise manipulation of the spiral 5 l.

The motion transmitting mechanism in this particular constructioncomprises a cam groove 83 formed upon the outer surface of the rotatablesleeve 58 which groove 63 is adapted to cooperate directly with a pin 64that is secured to the reciprocatory blade 42 whereby the back and forthmotion of the blade 42 is obtained. The stationary blade 4| is providedwith the longitudinal slot 65 to accommodate the pin 64 while the tube45 has a similar slot 66 for the same purpose. Substantially anyamplitude of motion between the stationary and reciprocating blade maybe obtained by the proper arrangement and design of the cam slot 63 andsleeve 58 as is apparent from the construction illustrated. And thus, bymanipulating the Wire 49 in an upward direction to allow spring 55 toreturn the spiral from the position to which the wire has moved thesame, sleeve 58 will be rotated within the horizontal tube 45 of thecutting implement with the cam slot 63 and the pin 64 transmitting suchrapid rotary motion of the sleeve 58 into a translated reciprocatorymotion through which the blade 42 is operated relatively to the blade 4Ito provide the cutting action. Such blades are also actuated at a rapidrate for a relatively slow rate of movement of the spiral 5|.

Referring now to Figs. 10, 11 and l2, a construction of cuttingimplement is here shown which is extremely simple having few operatingparts. Its construction also produces rapid relative reciprocation ofthe cutting blades with respect to each other with a correspondinglyslow manipulation of the handle or actuating elements. In the Fig. 10construction, the actuating mechanism is indicated at 10 for causing arapid relative movement between the cutting blades 'H and 12 through themotion transmitting mechanism indicated at 13. Blades 'Il and l2 areheld in cooperative cutting engagement through spring means 14, andblade 'H is connected to the housing 15 which is secured to one end ofthe waist level tube 15.-

An actuator 11 terminates in a spiral F8 which projects through andcoacts with a slot 18 in a rotatable sleeve 88 as best shown in Figs. l0l1. A suitable expansion spring 8! is interposed between the shoulderedportion 82 of the spiral i8 and any suitable stop plug 83 secured to thetube l5. This spring functions to move the spiral T8 downwardly wheneverthe actuator 'Il' has been drawn upwardly and released. Thusreciprocation of the spiral I5 in back and forth motion within tube 16causes rapid reversible rotation of the sleeve within the tube 16. Thesleeve 80 is provided with a disc or other suitable means 84 that bearsagainst the end of the tube 16 to prevent displacement of the sleeve 88upwardly with respect to the tube 16 during upward movement of theactuator 11. This disc 84 carries a crank pin 86 which operates within alateral slot 81 formed in the housing end 88 of 7 the movable blade 12,so that rotation of sleeve (i Ycauses -rapid reciprocation df 'the"movable blade 12 through the 'motion' transmitting vmeans justdescribed.

Downward displacement or the sleeve 8i) and its associated parts isprevented'by means of a bearing arm' secured to the end of the pin 8l'.The conical end`90 of the-bearing arm '89 seats `within-a depression 9|inthe housing 15 preventing relativegendwise movement'of the sleeve 80with Vrespect to the tube 16 at any time during the functioning ofspring 0| which normally acts downwardly ,upon Vthe spiral 18.Obviously, the conical end"9'0 of the'bea'ring arm 09 reacts ata pointwhi'ch'lies'on'the axial center line of the ent-ire operating 'mechanismwithin the tube 16 so that'v'ery little frctionisencountered at thispoint during the 'acticn of the mechanism and spring '0| since the disc8'4 engages a relatively -small surface area of theend 405 of the tube16, thefriction at this point is also relatively negligible. `The crankactionv and the manner in which the motion'is transmitted to the movableblade f2 4iro'm the actuating mechanism is'well shown in`Fi`g. 12 andneeds no additional explanation. Furthermore, the manner in which therotatable sleeve 80 is secured to the disc l84 is also optinal'althoughin this case such sleeve is indicated y'as staked at-points Sla to theldisc 8`4 vas shown in Fig. l2, producing a rigid union of theseparts.

Althoug'h'waistl level columnar vtubes have been described, itis obviousvthat short tubular columns can be supplied so that the tools may beused with 'the-hand disposed close to the ground 5?."

or for hedge trinmin'g purposes. This merely requires a condensation orrearrangement of the generalmechanism employed. For the short tubestructure;thebuttingy implement illustrated in Figs. 6A to `9 Vmay beconsidered most feasible in view ofthe fact that all of the actuatingmechanismis housed in a position directly adjacent the cutting bladesinstead of within the angularly disposed upwardly extending tube whichcarries -Yth'eha'nd grip members for operating the device.

The general structures of the three forms shown provide a goodrepresentation as to how the mechanisms of this invention may be adaptedto carry out their individual purposes in making a cutting implement ofa versatile nature in contrastto the cutting implements that are now inuse. YSome of ythe possible rearrangements of parts have been indicatedas they are obvious from the disclosure. i

Further, the cutting implements in Figs. 1B and 10 are constructed asrigid units wherein the cutting blades are disposed. and operated at aiixed angle with respect to the upwardly extending waist level tubesshown. However, a variation in the angle of the blades with respect tothe manipulating column may be desirable, and Figs. 6A and 7 incorporatemechanism to conveniently adjust the cutting plane of the blades withrespect to the manipulating column con-.

fspring pressed Ylatczhlll is `Asuitably-guidedY alongside the tube 43and is capable of engagement within 'any one of la number of notches Y98Vformed upon the periphery of one enlarged segmental ear '99 of 'theclevis 93.

Suitable operating means such as a release wire |00 can be connectedwith the spring latch 91 'atll to extend upwardly to the handle end ofthe tube 43. Here wire |00 passes through a suitablehole in a lugI |02on the handle 96 to be'secu'red to one leg v|03 of a pivoted bell crank|04. The other leg |05 is formed to provide a thumb knob for manualmanipulation. Leg |03 is normally held against the upper face of lug |02by the spring Ql'a of the latch means 91 acting through the wire |00when the latch is operatively seated in any selected one of thenotchesig of the segmental, ear 99. By a movement of the'thumb 'againstthe knob'leg |05 and inthe direction of the arrow |00, the adjustabledetent mechanism comprising the latch means SI-and ear A99 is releasedto allow resetting of the operating 'angle' of the cutting blades withthe actuating andmanipulating column of the cutter. Afterrelativemovement of tubes 43 and 45 about pivot pin 44 has properlypositioned the tubes, the detent mechanism may again be made eiectivebya release ofthe thumb knob |05 of the bellcrank |04,

The adjustablemech'anism and the operating parts therefor do notinterfere with the normal operationjof the hand manipulated members and05 and this mechanism is comparatively simple in construction. Otherequivalent detent means may be used in changing the angle between tubeand 45 with equal facility, and analogous arrangements might be appliedto the other described cutting implements. In the Fig. 6A construction,the slack'in the draw Wire |00 will at all times vbe taken up by thespring 55 regardless of the angular4 relationship between tubes 43 and.4,5.` Such slack will be comparatively negligible however.

It is contemplated that other modifications may be made in the exactstructures herein disclosed and'described as well as a substitution ofequivalent mechanism for performing the same functions as` do thosemechanisms submitted herewith.- All changes and rearrangements of thevarious mechanisms as well as other combinations of the parts shall becontrolled by the scope of the language of the appended claims submittedherewith'and directed to the present invention.

What I claim is:

vAn actuating vmelc'hanisni, for operating a movable element, saidlactuating mechanism comprising coacting spiral 'and slotted members,ymotivating means connected with one of 'said members to cause relativemovement between'both of said members, 'and motion trans-'mittingziechanisin connected with one oi said members and 'with saidmovable element to operatethe latter.

2. `An actuating mechanism for operating a movable unit, 'said actuatingmechanism comprising enacting spiral and slotted membersmo- 'tivating'means "connected with one of said members toY caus'e'relative movementbetween both of said memb'ersfand'motion transmitting mechanismconne'ctedbetween the other of Vsaid members and 'said movable unit tooperate the latter. said motion transmitting mechanism comprising areciprocatory'element having cam connection'withsaid other member andincludinga rockable connection-*between said reciprocatorj,7 element andsaid movable unit.

3. An actuating mechanism for operating a movable unit, said actuatingmechanism comprising coacting spiral and slotted members, manual meansconnected with one of said members to cause relative motion between bothof said members when said manual means is moved in one direction,cooperative means connected to urge said one member in the oppositedirection to impart further relative motion between said members, andmotion transmitting means connected with the other of said members andwith said movable unit and being directly responsive to the motion ofsaid other member to actuate said unit.

4. An actuating mechanism for operating a movable element, saidmechanism comprising a bodily movable spiral, a rotatable sleeve havinga slot therein for the reception of said spiral whereby bodily motion ofsaid spiral causes rotation of said sleeve, a rockable unit connectedwith said movable element to operate the latter, and

cam means interposed between said rotatable sleeve and rockable unit tomotivate the latter during the bodily movable action of said spiral.

5. An actuating mechanism to operate a movable element, said mechanismcomprising a bodily movable spiral, a rotatable sleeve having a slottherein for the reception of said spiral whereby bodily motion of saidspiral causes rotation of said sleeve, a rockable unit connected withsaid movable element to operate the latter, and cam means interposedbetween said rotatable sleeve and rockable unit to motivate the latterduring the bodily movable action of said spiral, saidk spiral includingmanual means to bodily urge the spiral in one direction, and resilientmeans connected to urge said spiral in the opposite direction.

6. An actuating mechanism to operate a movable reciprocable element,said mechanism comprising a bodily movable spiral, a rotatable sleevehaving a slot therein for the reception of said spiral whereby bodilymovement of spiral causes rotation of said sleeve, and motiontransmitting mechanism interposed between said sleeve and said movableelement to operate the latter, said motion transmitting mechanismincluding reciprocatory cam means arranged to impart reciprocatorymotion to said movable element upon rotation of said slotted sleeve.

7. A device to operate a movable member, said device comprising ahousing adapted 4to carry said t erable means carried by said extensionand connected with said actuating mechanism to operate the latter, meansconnecting said housing and said extension for relative swingingmovement, and adjustable coacting detent members interposed between saidhousing and said extension to selectively vary the relative positions ofthe housing with respect to the extension.

8. A device to operate a movable member, said device comprising a pairof housings, one of said housings carrying said movable member,actuating mechanism carried by one of said housings and connected foroperating said movable member, operable means carried by one of saidhousings and connected with said actuating mechanism to operate thelatter, means connecting said housings for relative swinging movement,and coacting adjustable latch members connected with each of saidhousings respectively to selectively 'vary the angular relation betweensaid housings.

9. An actuating mechanism to operate a movable element, said actuatingmechanism comprising coacting relatively movable spiral and slottedmembers, operative means connected with at least one of said members tocause relative movement between said members, and a pin oo nnected withthe other of said members for bodily rotation by said member, said pinbeing adapted for connection with said movable element to transmitmotion thereto.

EBERHARD E. WETTLEY.

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